This invention relates generally to a display monitor system for use in surgery or therapy, and more particularly to method and apparatus for providing an ophthalmic surgeon with the ability perpetually to monitor equipment status without diverting attention from the eye surgery by reflecting a coded visual image off of the cornea of the patient's eye. The preferred embodiment of the invention is described in the context of conventional aspiration, irrigation and phacoemulsification equipment used in cataract extraction surgery.
Heads up display systems presently are being used in aircraft instrumentation, whereby a pilot is provided simultaneously with a direct view of the path ahead of the aircraft and an indirect view, e.g. a projection onto the aircraft's windshield, of the status of critical aircraft equipment parameters. In this way, the pilot need not divert attention, even momentarily, from the immediate flight path in order also to monitor equipment and environmental parameters equally critical to reaching a destination. It is felt that, with regard to providing an aircraft pilot with information--especially during critical maneuvers--more is better.
Prevention of anterior chamber collapse during an ophthalmic surgical procedure requires not only the skill and dexterity, but also the close attention, of an experienced surgeon. Conventional aspiration, irrigation and emulsification equipment provide a front panel indication of such parameters as vacuum, pressure, and ultrasonic power level; and elapsed time, all of which must be closely monitored by the surgeon. In cataract extraction surgery, the surgeon simultaneously must manipulate two hand tools (one tool in each hand), one having an irrigation needle and the other having an aspiration needle and emulsification means (or one co-axial assembly which can provide irrigation, aspiration and emulsification and can be manipulated by one hand). Clearly, this is no time for the surgeon to divert attention from the field of operation, as is required by conventional monitoring equipment, especially during unassisted operation. Audible alarms, such as beepers, provide a distracting and imprecise form of feedback
It is desirable to provide `heads up,` or perpetual, display monitor method and apparatus for use in ophthalmic surgery that supplies the surgeon with any needed information regarding the condition of patient, eye or equipment, or other data pertinent to the procedure, without diverting the surgeon's attention from the region of the patient's eye. Because of the variety of data that has been found to be helpful in performing the surgery, the method and apparatus should be versatile enough to convey a large amount of information Because much of the information will regard conditions responsive to actions taken by the surgeon, and because minute delay can produce disastrous consequences, the method and apparatus should be able to provide feedback in real time response to those actions of the surgeon that are capable of affecting such conditions. Preferably, the method and apparatus would be easily adaptable to a wide range of conventional techniques and equipment, requiring little or no modification thereto.
Accordingly, it is a principal object of the present invention to provide a display monitor system that may be viewed by a surgeon without diverting the surgeon's attention away from the situs of the procedure being performed. Other important objects of the invention include the following:
(1) to provide a versatile system adaptable to a wide range of uses in providing constructive feedback to the surgeon;
(2) to provide a system, as described, that unobtrusively, but clearly, conveys information to the surgeon regarding the condition of patient, eye or external equipment;
(3) to provide a system the use of which requires little or no modification to existing techniques or equipment;
(4) to provide a system the image projecting part of which is lightweight, portable and easily manipulated by the surgeon;
(5) to provide a system the use of which relatively easily and quickly may be learned; and
(6) to provide a system that is reliable and inexpensive to use.